Re: Q - Cut and Paste Plate Glass
Owen, Phil (powen@analogic.com)
Mon, 03 Apr 95 15:05:00 EDT
In the latest issue of the "NASA tech. briefs" they wrote an article
specifying how they made a device to make a circular blank. Of course what
they are making is going into space so their spec got a little out of hand
(diameter accuracy better than .0001") but the design is very adaptable.
Briefly, the mirror is held in such a manner (pitch lap ?) that the edge can
be brought up to a belt sander and allowed to slowly rotate as the belt
sander does it job. They also described the flow of grits onto the work and
the amount of pressure to apply during the process. Of course you would want
to help out the process by knocking off the corners as Richard Hoffman
described in his earlier reply.
As for the pasting of 2 separate pieces of plate glass to get a thicker
objective...
Wouldn't the differing thermal properties (minute as they may be) of the 2
pieces of glass make the thing warp? Comments?
Phil....
powen@analogic.com